This invention relates to a MIXING DEVICE TO MIX GAS FUEL WITH AIR FOR INTERNAL COMBUSTION ENGINES, that is to say, a mixing device of the type that is interconnected in the air supply circuit towards the carburetor to produce a gas-air mix that is supplied for the explosions.
Most particularly the present invention covers a mixing device specially designed to act on the gas-air mix as a dosing dispenser of the fuel as well as a mixing chamber. Usually, internal combustion engines operate using liquid fuel, thus requiring devices usually referred to as carburetors, the function of the latter is to spray the liquid that will enter into the combustion chamber, dosing it in the necessary ratio for each case and mixing it with a carbureting substance that is precisely ambient air previously filtered prior to its entrance to the carburetor.
Currently the trend is to replace said liquid fuels by gaseous fuels such as liquefied gasxe2x80x94xe2x80x9cCLGxe2x80x9d; propane; butane or else compressed natural gasxe2x80x94xe2x80x9cCNGxe2x80x9d. Further, many vehicles offer the possibility to alternate between both types of fuels (liquid and gaseous), thus resorting to special fuel selector devices.
Several devices of this type are well known, all of them to be engaged in the conduits supplying filtered air towards the carburetor. Some of them are even designed to be incorporated on the carburetor itself over the throttle rod butterfly fins.
In some cases these are picks which are transversely inserted in the air flow passage way, as disclosed in Argentine Patent No. 238-686 property of the company: AMOS GAS MIXERS L.T.D. Specifically, in this document it is mentioned the problem of those gas dispensers and mixers consisting of cylindrical tubes transversely extending towards the interior of the carburetor. It is stated that the mixture is sometimes too rich, thus increasing the carbon settlings inside the combustion chamber. A pick extending across the air inlet conduit into the carburetor is therein proposed and the invention is conditioned to some construction specifications specially created so that the mixture produced be always the most adequate to meet the needs of the engine. It is therein emphasized that the gas dispensing opening is located in the longitudinal central axis of the above mentioned inlet conduit to the carburetor and that the upper face of the above mentioned nozzle is substantially flat while its oblique opening is oriented downwards.
Likewise, other mixing and dispensing devices are well known, many of them of Italian origin, consisting of hollow tubular bodies that are coaxially inserted to the referred filtered air passageway towards the carburetor. All of them operate taking advantage of the draught generated by said air flow towards the carburetor, which also carries the gas fuel which is mixed with said flow so that the greater the requirement of the engine, the greater the airflow to be used and therefore the greater amount of gas to be carried and mixed.
Several different embodiments corresponding to the operation principles stated hereinbefore are well known, since the mixture that can be obtained is very adequate under any operating condition in which the engine is to be used.
These well-known mixing devices are coaxially arranged and in direct communication with the entrance opening to the carburetor and they consist of a hollow tubular body that includes an internal tube in the form of a truncated cone coaxially arranged, which upper base -open and of a smaller diameter-faces the air inlet to the mixer. Likewise, its lower basexe2x80x94bigger in diameter-corresponds to the exit opening of the same hollow tubular body. The mixer is completed with a lateral connector pick that projects outwards from the same hollow tubular body so as to connect to the gas feeding conduit.
In said well-known mixing devices, the above mentioned gas feeding pick allows the entrance of fuel towards an annular chamber that is defined between the walls of said internal hollow body in the form of a truncated cone and the cylindrical wall of the tubular body. This chamber is very useful so that the mixer keeps a minimum gas level arranged to be mixed.
Said annular chamber remains communicated to the filtered air flow through a circumferential opening that conforms in correspondence with the junction between the open upper base and with a lower diameter of the internal body in the form of a truncated cone and the air inlet opening of the hollow tubular body.
It is pointed out that this being a circumferential opening that allows the gas inlet to the filtered air flow, the mix is very homogeneous and direct, so that when the suction is greater there will always exist greater volume of gas to be homogeneously mixed.
However, when using the mixing devices in a generalized manner, some difficulties have arisen, among others we can mention those related to the gas flow required for each case or type of engine.
In fact, one difficulty is that in many cases the mixing device interferes with the air passageway to the carburetor, thus producing non-desired vortexes or chokes especially when the air is required to be mixed with liquid fuel.
Other detected difficulty is that many times the mixer design does not assure that the air inlet is kept constant, above all when the engine consumes liquid fuel.
Other detected difficulty is the great variety of formats and sizes existing in the market, as a consequence of the great amount of models and types of vehicles that appeal to this option of including gas dispensers and mixers. The existing ones are not versatile at all and therefore they can only be adapted to very few models or types of engine.
Other difficulty is that the positioning of the pieces and elements that form part of the mixer cannot be easily regulated so as to position them according to the requirements of use. Above all, the work of the specialized mechanics is particularly difficult and there are even many mixers that do not allow an adjustment of the regulation when already in use.
The mixing device this invention refers to belongs to the group that applies the above mentioned coaxial hollow body in the form a truncated cone seated inside a cylindrical body, so that a pick projected outwards from the cylindrical body allows the gas inlet towards an internal chamber that is defined between both bodies.
However, the created device stands up since it holds some building characteristics of its own with which the above indicated problems are clearly solved.
These modifications are expressly oriented to ease the gas flow regulation work that enters the mixing sector. Said work will be very simple and direct so as to simplify the work of the installer and also in case of having to perform modifications to the same when already in use.
Likewise, these building modifications will incorporate means that will be specially used to keep in a very stable condition the relative positioning of the pieces and elements of the mixer during said regulation work.
Consequently, the main objective of this invention patent is a MIXING DEVICE OF GAS FUEL WITH AIR FOR INTERNAL COMBUSTION MOTORS, apt to be inserted in an air supply conduit to the carburetor, in coaxial arrangement and in direct communication with air inlet conduit of the same carburetor, of the type that comprises a cylindrical and hollow external body inside which it is seated a hollow body in the form of a truncated cone, the open base of the same having a smaller diameter faces the air inlet opening that defines said external cylindrical body, in such a manner that its open bigger base corresponds with the outlet opening of the same external cylindrical body, being the set completed with a lateral connector pick that projects itself outwards from the same external cylindrical body, conforming in this way an annular chamber of gas fuel supply, defined between the walls of both coaxial bodies, that communicates with the internal sector of the device through an opening defined by separation that is determined from the upper edge of the smaller base of the internal body in the form of a truncated cone. The invention stand out due to the fact that cylindrical and hollow external body presents threaded internal sections near its upper and lower open bases; said threaded sections are the removable mean of setting of a threaded ring for the regulation of the gas input and of the above mentioned internal body in the form of a truncated cone that, for that purpose, has an external thread near its bigger open base as well as a connecting pick that is related to the same external cylindrical body by threading; completing the set with at least one pair of setscrews that go through the cylindrical wall of the external body to face, respectively, with the threaded sections of the internal body in the form of a truncated cone and with the regulation ring.
Likewise, the threaded internal sections of the external cylindrical body are of the same diameter as the external threading of the body in the form of a truncated cone.
On the other hand, it is additionally highlighted that the communication opening of the annular chamber defined between the walls of both coaxial bodies is determined by the separation between each other of the threaded ring and the body in the form of a truncated cone.